出现的错误：
ERROR 1205 (HY000): Lock wait timeout exceeded; try restarting transaction
解决办法：
查看sleep的进程
MySQL> show full processlist; ------- ---------- ------------------- ---------- --------- ------- ---------- ----------------------------------------------------------------------------- | Id | User | Host | db | Command | Time | State | Info | ------- ---------- ------------------- ---------- --------- ------- ---------- ----------------------------------------------------------------------------- | 32579 | official | 127.0.0.1:42690 | official | Sleep | 20926 | | NULL | | 32715 | erp | 127.0.0.1:2078 | NULL | Sleep | 4570 | | NULL | | 32716 | erp | 127.0.0.1:2079 | erp | Sleep | 3590 | | NULL | | 32717 | erp | 127.0.0.1:2080 | erp | Sleep | 3577 | | NULL | | 32732 | erp | 127.0.0.1:2081 | erp | Sleep | 3590 | | NULL | | 32733 | erp | 127.0.0.1:2082 | NULL | Sleep | 1412 | | NULL | | 32734 | erp | 127.0.0.1:2083 | erp | Sleep | 1160 | | NULL | | 32735 | erp | 127.0.0.1:2084 | erp | Sleep | 985 | | NULL | | 32736 | erp | 127.0.0.1:2085 | erp | Sleep | 1160 | | NULL | | 32739 | erp | 127.0.0.1:2088 | erp | Sleep | 695 | | NULL | | 32740 | erp | 127.0.0.1:2089 | erp | Sleep | 768 | | NULL | | 32741 | erp | 127.0.0.1:2090 | erp | Sleep | 688 | | NULL | | 32742 | erp | 127.0.0.1:2091 | erp | Sleep | 686 | | NULL | | 32743 | erp | 127.0.0.1:2092 | erp | Sleep | 687 | | NULL | | 32745 | erp | 127.0.0.1:2093 | erp | Sleep | 686 | | NULL | | 32746 | erp | 127.0.0.1:2094 | erp | Sleep | 686 | | NULL | | 32763 | root | localhost | erp | Query | 0 | starting | show full processlist | | 32765 | erp | 127.0.0.1:58216 | erp | Sleep | 18 | | NULL | | 32766 | erp | 127.0.0.1:58218 | erp | Sleep | 41 | | NULL | | 32767 | erp | 127.0.0.1:58220 | erp | Sleep | 41 | | NULL | | 32768 | erp | 127.0.0.1:58222 | erp | Sleep | 41 | | NULL | | 32769 | erp | 127.0.0.1:58224 | erp | Sleep | 2 | | NULL | | 32770 | erp | 127.0.0.1:2106 | NULL | Sleep | 153 | | NULL | | 32771 | erp | 127.0.0.1:2107 | erp | Sleep | 148 | | NULL | | 32772 | erp | 127.0.0.1:2108 | erp | Query | 18 | updating | UPDATE `erp_user` SET `pwd`='OyUHgt21gTP2/5uFgbKZtq==' WHERE (`id`='10113') | ------- ---------- ------------------- ---------- --------- ------- ---------- -----------------------------------------------------------------------------
没有看到正在执行的慢SQL记录线程，再去查看innodb的事务表INNODB_TRX，看下里面是否有正在锁定的事务线程，看看ID是否在show full processlist里面的sleep线程中，如果是，就证明这个sleep的线程事务一直没有commit 或者 rollback而是卡住了，我们需要手动kill掉。
mysql> SELECT * FROM information_schema.INNODB_TRXG; *************************** 1. row *************************** trx_id: 20342 trx_state: RUNNING trx_started: 2018-01-29 16:48:13 trx_requested_lock_id: NULL trx_wait_started: NULL trx_weight: 4 trx_mysql_thread_id: 32735 trx_query: NULL trx_operation_state: NULL trx_tables_in_use: 0 trx_tables_locked: 1 trx_lock_structs: 2 trx_lock_memory_bytes: 1136 trx_rows_locked: 1 trx_rows_modified: 2 trx_concurrency_tickets: 0 trx_isolation_level: REPEATABLE READ trx_unique_checks: 1 trx_foreign_key_checks: 1 trx_last_foreign_key_error: NULL trx_adaptive_hash_latched: 0 trx_adaptive_hash_timeout: 10000 trx_is_read_only: 0 trx_autocommit_non_locking: 0 1 row in set (0.00 sec)
ERROR: No query specified
看到有这条 32735 的sql，kill掉，执行kill 32735; kill 32735;
然后再去查询INNODB_TRX表，就没有阻塞的事务sleep线程存在了，如下所示： mysql> SELECT * FROM information_schema.INNODB_TRXG;
Empty set (0.00 sec)
现在可以正常执行 sql 语句了
